I. Field of the Invention
The present invention relates generally to the field of song bird feeders and, more particularly, to bird feeders which prevent unwanted rodents and birds from feeding at the feeder. The feeder of the present invention also provides a great deal of amusement to those watching when an unwanted rodent alights on the feeder.
Bird watching is a fulfilling activity for many and provides an educational tool for children in that it increases environmental consciousness. Further, bird feeders assist certain species of birds to find foods and supplements to augment their diets, especially during periods of severe weather.
II. Description of the Related Art
Not only are there many bird feeders of unlimited designs, there are also bird feeders which have been designed to prevent unwanted birds and rodents from invading and eating from bird feeders which have been designed for the typical lightweight song bird.
The prior art has disclosed many devices to effect the discouragement or removal of unwanted pests at the song bird feeder. For instance, there are a great number of weight sensitive, tiltable perches on bird feeders for dislodging the unwanted pest such as shown in the patents to Loken (U.S. Pat. No. 5,105,765), Wessner (U.S. Pat. No. 5,048,461) and Dehls (U.S. Pat. No. 4,541,362).
There are many electrical type devices which will shock unwanted pests which alight on a song bird feeder, such as is shown in Fry (U.S. Pat. No. 5,392,732) and Collins (U.S. Pat. No. 5,471,951).
Many weight sensitive devices have been shown wherein the food openings in the bird feeder will close if a heavier rodent than the normal song bird sits on the perch near the food opening. The patent to Drakos (U.S. Pat. No. 5,720,238) is typical of this type of mechanism.
There are also devices which sense a rodent, such as a squirrel or heavy unwanted bird, which will, at a predetermined point in time, effectively remove the unwanted pest from the feeder. Typical of these prior devices, is the patent to Hibbard (U.S. Pat. No. 5,297,503) and Korb (U.S. Pat. No. 5,690,056).
It is to the type of feeders which utilize weight sensitive, tiltable perches to which the present invention pertains.
In accordance with the present invention and the contemplated problems which have existed and continue to exist in this field, the objectives of this invention include providing a pest proof song bird feeder. The feeder of the present invention is mechanical in nature and presents several embodiments of the basic design.
The present invention generally includes spring loaded elongated cylindrical perches incorporated into bird houses and/or bird feeders (the terms are used interchangeably herein), wherein the perches have a typically round perch member which, when loaded by an undesirable bird or other pest, will sense the weight of the pest and the weight will overcome the spring loaded perch and the perch will collapse at a fulcrum point thereby dislodging the bird or pest. It should be noted that, while round perches are convenient, they do not exclude other configurations from the scope of this invention.
The spring which is utilized with the perches is designed to have the capability of elongating upon the application of a predetermined force being applied to the spring by means of the weight of the pest on the perch, and then the spring will elongate causing the perch to bend vertically downward with respect to the ground dislodging the pest, and when the longitudinal force on the spring is relaxed, the spring then resumes its relaxed length and draws the perch back into battery with respect to the spring housing assembly.